1. Technical Field
The present invention relates to a method using a blank for an absorbent article in the form of diaper pants or a sanitary panty in order to produce such an article, which blank includes an absorbent body enclosed between an inner, liquid-permeable cover sheet and an outer cover sheet, at least one cover sheet being made of a material which can be thermally welded, which blank further has a front portion, a rear portion, and a crotch portion which extends between these portions and includes and is delimited by the leg openings of the blank, said front portion and rear portion having side parts which extend laterally outside the absorbent body from the waist band to the leg openings. The invention also relates to an article of the disposable type produced by means of this method.
2. Related Art
Diaper pants are an alternative to open type diapers and have become increasingly popular for slightly older infants. Today's diaper pants have a good fit, which contributes to ensuring that they function well and which in addition gives them an aesthetically attractive look. Unlike conventional open diapers which look like pants once they have been fitted on the user, diaper pants look like pants right from the start, because the manufacturer has joined the side-edge portions of the front and rear portions of the diaper together. Diaper pants are easy to change with the user standing, by pulling them down just like underpants and then putting on a new set of diaper pants. U.S. Pat. No. 3,604,015 discloses diaper pants in which a blank with front and rear portions of the same width is folded about a transverse line in the crotch portion, after which the edge portions of the folded blank which have been laid on one another are sewn together. Such a connection between the side-edge portions protrudes like a flange from the diaper pants and detracts from their appearance. To improve the appearance, these known diaper pants are produced by a method in which, in a final stage, the blank for the diaper pants is turned inside out so that said flange is situated on the inside of the diaper pants and does not therefore spoil the appearance of the diaper pants. A disadvantage of such a flange connection is that it is exposed to forces (peel forces) directed at right angles to the connected surfaces and for this reason it must be very strong.
WO 99/44559 and U.S. Pat. No. 5,607,537 disclose methods of producing flangeless seams and thereby avoiding peel forces. However, these seams comprise many material layers and are therefore bulky.
It is difficult to pull the diaper pants off when the user is lying down. If the diaper pants contain excrement, it is virtually impossible to pull the diaper pants off without soiling the user or his/her clothes. To solve this problem, it is known to design diaper pants such that they can be opened along the sides in the same way as conventional open diapers. For example, from EP-B1-0 755 238 it is known to connect the side-edge portions of the front and rear portions with the aid of detachable and resealable fastenings. From GB-A-2 267 024 it is known to arrange weakening lines in the side portions of the diaper pants in order to allow the diaper pants to be opened, and the diaper pants in EP-A2-0 187 728 have side seams which can be torn open.